A prerequisite for a synthetic description of the learning and memory (LM), neural bases is a model of the brain. The model we have adopted is based on functional anatomy and consists of three interacting systems. The first, R for representation, is made of the neurons which code sensory information or motor programs with the highest precision. The second, A for activation, comprises the neurons which are most directly involved in arousal and motivation. The third system, S for supervision, controls goal-directed behaviors. The best illustration of its functions is the “voluntary act” in humans: it involves a representation of a goal and of the appropriate strategies, the evaluation of the results and the correction of errors.
The memory system is not an anatomically separate entity but a set of interactions between R, A and S. In these interactions, the three systems have different though complementary functions. R is mainly involved in encoding and storage. S plays a role in encoding and retrieval through the control of attention and cognitive strategies. Structures of A, which modulate R and S activities, are involved in all stages of memory processes. Different types of LM set into play different types of interactions between R, A and S.
Within this general scheme, we considered data from different levels of organization, from the whole brain to the molecule, through intermediates such as small networks (for example, the cortical column). Finally, an attempt is made at defining the perspectives for future research. Among its main objectives are the integration of LM bases in the neurobiology of the whole behavior, the genetic and developmental factors, new therapies for improving memory in aged and demented people, the design of formalisms able to represent large-scale neural networks.